Justification:
Endemic to Lake Malawi, Lake Malombe and the Shire River. This species has experienced declines of more than 70% in the last 10 years as indicated from fisheries catch statistics. Information on the status of this species is available mainly for Lake Malawi, the Upper Shire and Lake Malombe (but it should be noted that direct observation finds that even in other parts of the Shire River chambo catches have declined over the past 10 years). The total chambo catch (for Lake Malawi, Upper Shire and Lake Malombe combined) in 1980 was 10,711 tons, increasing to 17,439 tons in 1982. However, by 1990 it had declined to 6,483 dropping further to 2,774 tons in 1996. This infers a reduction of more than 70% in the catches over a ten-year period. Further monitoring in southern Lake Malawi has found that chambo stocks have continued to decline at the same rate during 1994–1999. On the basis of this continuing decline the species is assessed as Endangered.

During the 1950s over 3,000 tonnes of Chambo per year (chiefly O. squamipinnis) were being taken from Lake Malawi's southeast arm alone. However, the total catch for chambo in this part of the lake has shown a steady decline since early 1990s. CPUE in the main harvesting fisheries has also declined dramatically due to over-fishing.In Lake Malombe chambo catches were around 4,000 tons in the late 1970s, increasing to over 6,000 tons in the early 1980s. In the late 1980s a drastic decline was observed with catches falling to less than 600 tons per year by the early 1990’s and to less than 200 tons in the late 1990’s. This decline in total catch in Lake Malombe is directly matched by severe declines in CPUE in the two main fisheries harvesting the stock, namely gill nets and chambo seines. The Chambo stocks in Lake Malombe are considered to have been in a state of collapse or near collapse since the early 1990s.

This is one of the three 'Chambo' species endemic to Lake Malawi. Like other species of the subgenus Nyasalapia, males of O. karongae develop long branched genital 'tassels' that serve as egg dummies. Territorial male O. karongae are jet black, with a white dorsal fin margin. O. karongae can be seen in loose shoals in many areas of the lake. They feed by rasping the surfaces of rocks and weeds and by sifting sediment and also feeding in the water column. They eat mainly algae, detritus and zooplankton. The breeding season runs from July to March, peaking around September and again in February. In Lake Malombe there is just a single peak around July to October. Like other Oreochromis they are maternal mouthbrooders. Males dig large spawning platforms in waters ranging from the shallows down to depths of at least 28 m. Like other chambo, they construct a slightly raised bowl-shaped central spawning cone inside the larger pit. Max. size: 37 cm TL.